Support boom to attach planar array antenna to mast

ABSTRACT

AN ANTENNA ASSEMBLY COMPRISING A SUPPORTING BOOM, MEANS FOR RIGIDLY CLAMPING THE SUPPORT BOOM TO A MAST, SUPPORT MEANS DISPOSED AT EACH END OF THE SUPPORT BOOM, A MAIN BOOM, AND AT LEAST ONE ANTENNA FIELD ELEMENT CARRIED BY THE MAIN BOOM, THE SUPPORT MEANS BEING PROPORTIONED AND DESIGNED TO SUPPORT THE MAIN BOOM ON THE SUPPORT BOOM. MEANS IS PROVIDED FOR RIGIDLY CLAMPING THE MAIN BOOM TO SUCH A MAST WHILE THE MAIN BOOM IS SUPPORTED BY THE SUPPORT MEANS. IN A PREFERRED EMBODIMENT OF THE INVENTION, EACH OF THE SUPPORT MEANS COMPRISES AN INSULATIVE, H-SHAPED MEMBER, THE LOWER LEGS OF WHICH ARE PROPORTIONED AND DESIGNED RECEIVABLY TO ENGAGE THE SUPPORT BOOM AND THE UPPER LEGS OF WHICH ARE PROPORTIONED AND DESIGNED RECEIVABLY TO ENGAGE A PORTION OF THE MAIN BOOM. ALSO, PREFERABLY, THE SUPPORT BOOM AND MAIN BOOM HAVE SUBSTANTIALLY SQUARE, OR AT LEAST RECTANGULAR, CROSS SECTION AND THE LOWER AND UPPER LEGS OF THE H-SHAPED MEMBERS SNUGLY ENGAGE, RESPECTIVELY THE SIDES OF THE SUPPORT BOOM AND THE MAIN BOOM.

Feb. 2, 1971 L oc woog 3,560,987

SUPPORT BOOM TO ATTACH PLANAR ARRAY ANTENNA TO MAST Filed May 27, 1968 LYNN L.Loci wooo,

ATTORNEYS.

United States Patent Office 3,560,987 Patented Feb. 2, 1971 US. Cl. 343-880 3 Claims ABSTRACT OF THE DISCLOSURE An antenna assembly comprising a support boom, means for rigidly clamping the support boom to a mast, support means disposed at each end of the support boom, a main boom, and at least one antenna field element carried by the main boom, the support means being proportioned and designed to support the main boom on the support boom. Means is provided for rigidly clamping the main boom to such a mast while the main boom is supported by the support means. In a preferred embodiment of the invention, each of the support means comprises an insulative, H-shaped member, the lower legs of which are proportioned and designed receivably to engage the support boom and the upper legs of which are proportioned and designed receivably to engage a portion of the main boom. Also, preferably, the support boom and main boom have substantially square, or at least rectangular, cross sections and the lower and upper legs of the H-shaped members snugly engage, respectively, the sides of the support boom and the main boom.

BACKGROUND OF THE INVENTION Field of the invention The present invention relates to antenna assemblies of the type which are conventionally mounted on upstanding masts, and more particularly to the provision of an improved antenna assembly which is constructed to be more conveniently mounted on such a mast.

Description of the prior art conventionally, antenna assemblies comprise a boom or frame on which a plurality of antenna field elements such as dipoles, directors and reflectors, are mounted and means for rigidly clamping such a boom directly to an upstanding mast. Conventionally, such upstanding masts are usually aluminum or steel pipes which are anchored at their lower end to extend vertically upwardly. The means for clamping the boom to the mast is conventionally a U-bolt assembly.

One problem. with such conventional antenna assemblies is that they are difiicult for a single person to install. Typically, an installer mounts the mast on a roof so that it extends vertically upwardly and then the installer carries the boom or frame with the antenna field elements mounted thereon upwardly onto the roof and clamps it to the mast. Since the installer must hold the boOm with one hand while he installs and tightens the U-bolt assembly with his other hand, he cannot hold on to a support to steady himself. In many cases the booms will be up to ten feet long or longer and the antenna field elements will be, typically, six feet long. In such cases, if the wind is at a high velocity, the boom is diflicult to hold with one hand. Of course, in the winter, the installers problems can also be compounded by the presence of ice on the roof.

The antenna assembly of the present invention solves these installation problems. Specifically, the antenna assembly of the present invention is so constructed that it can be easily and safely installed by one person.

SUMMARY OF THE INVENTION The present invention is an improved antenna assembly wherein the improvement resides in the provision of a selfsupporting frame or support boom which is arranged to be rigidly clamped to a mast and to support a main boom or frame, i.e., the boom on which the antenna field elements are mounted, while it is being clamped to the mast. This support boom, which may typically be thirty inches in length, is relatively easy, because of its small size, to clamp to a mast.

In the preferred embodiment of the present invention, an insulative support means is disposed at each end of the support boom and arranged to support the main boom with supported frame on the support boom with self-supporting frame. Also, preferably, each such insulative support means is fastened to the support boom and provided with an upwardly opening notch for receivably engaging and cradling a portion of the main boom. Further, preferably, the main boom and the support boom have square cross sections and each insulative member is an H-shaped member, the upper and lower legs of which are proportioned and arranged snugly to engage the fiat sides, respectively, of the main boom and the support boom.

It is a primary object of the present invention, therefore, to provide an antenna assembly which can be easily installed by one person.

Another object of the present invention is to provide such an antenna assembly which, after it is installed on a conventional mast, will be more securely fastened to the mast.

Other objects and features of the present invention will become apparent as this description proceeds.

The above-mentioned and other features and objects of this invention and the manner of attaining them will become more apparent and the invention itself will be best understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings wherein:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of the antenna assembly of the present invention installed on a conventional mast;

FIG. 2 is a fragmentary, exploded perspective view showing the support boom clamped to the mast;

FIG. 3 is an enlarged, sectional view taken from FIG. 1 generally along the line 3-3; and

FIG. 4 is a perspective view of the antenna assembly mounted on the mast.

DESCRIPTION OF THE PREFERRED EMBODIMENT The antenna assembly of the present invention, indicated generally by the reference numeral 10, comprises a support boom or self-supporting frame '12, a main boom or supported frame 14 on which conventional antenna field elements 16 are mounted, a support member 18, 20 securely fastened to each end of the support boom 12 by means such as the illustrated rivets 22, a U-bolt assembly 24 for clamping the support boom to a conventional mast 2'6 and another U-bolt assembly 28 for clamping the main boom to the mast. These U-bolt assemblies 24, 28 are conventional and need not be discussed, in detail, in this description. Similarly, the elements 16 are conventional and any desired combination of dipoles, directors and reflectors may be mounted on the main boom 14 without departing from the scope of this invention.

In the illustrative embodiment, the support boom 12 and main boom 14 are fabricated from tubular aluminum stock having a substantially square cross section, the advantage of which will be discussed hereinafter.

Each support member or locating element 18, 20 is preferably an H-shaped member having upwardly extending legs 30 defining an upwardly opening notch 32 and downwardly extending legs 34 defining a downwardly opening notch 36, these notches having a cross sectional shape such as that illustrated in FIG. 3. Each member 18, 20 can be a rather inexpensively plastic molded part which will not add, significantly, to the total cost of the antenna assembly 10.

The lower legs 34 of each member 18, 20 are spaced apart and arranged snugly to engage respectively the vertical sides of the lower boom 12 such that, when the member is fastened to the boom by a rivet 22, a rigid locating and support means for the main boom 14 is provided. Similarly, the upper legs 30 defining the notch 32 are arranged respectively to engage the opposite vertical sides of the main boom 14 to hold the main boom against movement relative to the support boom 12. The snugness with which the main boom 14 is receivably engaged by the notch 32 is such that the main boom can easily be lowered or placed in the notch, but yet sufficiently tight to prevent significant lateral or longitudinal movement of the main boom. In some cases, it may be desirable for the legs 30 snugly to engage the main boom, in which cases, the installer can place the main boom in the notches 32 of the support members 18, 20 and leave the main boom cradled in these notches while he performs other functions, such as connecting the wiring of the antenna assembly, and before he uses the U-bolt assembly 28 to clamp the main boom to the mast 26.

An attractive feature of the support boom 12 is that amplifiers, baluns, and other accessories, such as the illustrated television lead connector 38, may be mounted on the support boom before it is clamped to the mast 26. All of such accessories can be interconnected before the main boom is carried upwardly onto the roof and placed upon the support boom 12. Then, the only remaining task is to connect the antenna leads to the connector box 38.

In summary, it will be apparent that an installer can clamp or fasten the support boom or self-supporting frame 12 to the mast 26 and synchronize it with the antenna rotor supporting the mast, if there is such a rotor, make the necessary electrical connections for the accessories mounted on the support boom, and then set the main boom with supported frame 14 in place on the support members 18 and 20. The installer is thus free to tighten the U-bolt assembly 28 with one hand while steadying himself with the other hand. If the mast 26 is stationary, i.e., not mounted on a rotor, the support boom 12 and the main boom 14 must be properly oriented about the axis of the mast. That is, the field elements 16 must be properly oriented relative to the transmission station or stations emanating signals to be received by the antenna assembly. In such a case, the main boom 14 can be properly oriented relative to such stations by placing it on the support boom 12 and connecting its leads to a receiver, such as a television receiver, and then, by loosening the U-bolt assembly 24, adjustably moving the main boom about the axis of the mast 26. After the main boom 14 is properly oriented, the U-bolt assembly 28 can be tightened firmly to clamp the main boom in its properly oriented position.

As stated previously, conventionally, the boom on which the antenna field elements are mounted is merely clamped by means such as one of the U-bolt assemblies 24, 28 to a mast. In the present case, the main boom 14 is not only clamped to the mast 26 by the U-bolt assembly 28, it is supported over a substantial portion of its length by the support boom 12. Thus, since the U-bolt assemblies 24, 28 can be snugly tightened and since the support members with locating means 18, 20, which are rigidly mounted on the support boom can be made snugly to engage portions of the main boom 14, the antenna assembly 10 can be very rigidly fastened to the mast 26. The combination of the two- U-bolt assemblies 24, 28 and the rigidity of the short length of the support boom 12 will tend to resist pivotal movement of the main boom 14 relative to a horizontal plane.

While there have been illustrated and described a support boom with self-supporting frame 12 and main boom with supported frame 14 having square cross sections, it will be understood that the present invention is not limited to such cross sectional shapes and that booms having circular cross sections may be used. Of course, one of the major problems with a boom having a circular cross section is that it will tend to revolve about its axis. Likewise, booms having non-square or, perhaps, rectangular cross sections may be used in the antenna assembly of the present invention.

While there have been discussed above the principles of this invention in conjunction with specific apparatus, it is to be clearly understood that this description is made by way of example and not as a limitation to the scope of the invention.

What is claimed is:

1. An antenna assembly comprising a self-supporting frame and a supported frame, said supported frame including at least one antenna field element, means for rigidly clamping said self-supporting frame to a mast, a plurality of locating elements carried by one of said frames, said locating elements each having at least one surface for positioning and at least one surface for supporting and positioning one of said frames relative to the other of said frames, means for rigidly clamping said supported frame to a mast while said supported frame is being supported by said self-supporting frame, each of said locating elements comprising an insulator carried by said self-supporting frame, said insulator having an upwardly opening recess therein proportioned to receive a portion of said supported frame in said recess.

2. An antenna assembly comprising a self-supporting frame and a supported frame, said supported frame including at least one antenna field element, means for rigidly clamping said self-supporting frame to a mast, a plurality of locating elements carried by one of said frames, said locating elements each having at least one surface for positioning and at least one surface for supporting and positioning one of said frames relative to the other of said frames, each of said locating elements comprises an insulator carried by said self-supporting frame, said insulator having an upwardly opening recess therein proportioned to receive a portion of said supported frame in said recess, and a downwardly opening recess therein proportioned to receive a portion of said selfsupporting frame in said recess, means for rigidly fastening each of said locating elements to one of said frames, and means for rigidly clamping said supported frame to a mast.

3. The antenna assembly of claim 2 in which said self-supporting frame and said supported frame have substantially square cross sections and in which said recesses have oppositely facing upstanding sides proportionately spaced to receive therebetween and snugly engage, respectively, the opposite sides of said self-supporting frame and said supported frame.

(References on following page) 5 References Cited I UNITED STATES PATENTS Winegard 343-815 Liu 343-811 Bell et a1. 343816 Brown 343-819 Flanagan 343758 6 FOREIGN PATENTS 4/1963 France 343--817 4/1953 Great Britain 343-819 5 ELI LIEBERMAN, Primary Examiner U.S. C1. X.R. 

